Comprehensive characterization of central BCL-2 family members in aberrant eosinophils and their impact on therapeutic strategies

Purpose Hypereosinophilia represents a heterogenous group of severe medical conditions characterized by elevated numbers of eosinophil granulocytes in peripheral blood, bone marrow or tissue. Treatment options for hypereosinophilia remain limited despite recent approaches including IL-5-targeted monoclonal antibodies and tyrosine kinase inhibitors. Methods To understand aberrant survival patterns and options for pharmacologic intervention, we characterized BCL-2-regulated apoptosis signaling by testing for BCL-2 family expression levels as well as pharmacologic inhibition using primary patient samples from diverse subtypes of hypereosinophilia (hypereosinophilic syndrome n = 18, chronic eosinophilic leukemia not otherwise specified n = 9, lymphocyte-variant hypereosinophilia n = 2, myeloproliferative neoplasm with eosinophilia n = 2, eosinophilic granulomatosis with polyangiitis n = 11, reactive eosinophilia n = 3). Results Contrary to published literature, we found no difference in the levels of the lncRNA Morrbid and its target BIM. Yet, we identified a near complete loss of expression of pro-apoptotic PUMA as well as a reduction in anti-apoptotic BCL-2. Accordingly, BCL-2 inhibition using venetoclax failed to achieve cell death induction in eosinophil granulocytes and bone marrow mononuclear cells from patients with hypereosinophilia. In contrast, MCL1 inhibition using S63845 specifically decreased the viability of bone marrow progenitor cells in patients with hypereosinophilia. In patients diagnosed with Chronic Eosinophilic Leukemia (CEL-NOS) or Myeloid and Lymphatic Neoplasia with hypereosinophilia (MLN-Eo) repression of survival was specifically powerful. Conclusion Our study shows that MCL1 inhibition might be a promising therapeutic option for hypereosinophilia patients specifically for CEL-NOS and MLN-Eo.

Rituximab Treatment in a Patient with Kimura Disease and Membranous Nephropathy: Case Report

Kimura disease (KD) is a chronic, inflammatory disorder with slowly developing subcutaneous tumor-like swellings, often occurring in the head and neck region. KD is diagnosed based on histology, elevated levels of immunoglobulin type E, and increased peripheral eosinophil granulocytes. KD may coexist with glomerular renal diseases, and this case report is based on a patient with KD-associated membranous nephropathy. Patients with membranous nephropathy without KD have demonstrated responsiveness to treatment with monoclonal anti-CD20 antibodies. This case report is the first to investigate the effect of rituximab treatment in a patient with KD-associated membranous nephropathy. A 30-year-old Italian man living in Denmark was diagnosed with Kimura’s disease based on subcutaneous nodules with eosinophil angiolymphoid hyperplasia. The patient was admitted to the hospital due to nephrotic syndrome. Serology showed eosinophil granulocytosis and negative PLA2-receptor antibody. Renal biopsy showed membranous nephropathy, and the patient was treated with systemic methylprednisolone followed by cyclosporin and then cyclophosphamide with only partial remission. Ultimately, treatment with intravenous rituximab was initiated, which resulted in overall remission and no nephrotic relapses at 30 months of follow-up. Thus, intravenous rituximab effectively decreased proteinuria and prevented nephrotic relapses in a patient with treatment-refractory membranous nephropathy due to KD.

Eosinophils are dispensable for development of MOG35-55-induced experimental autoimmune encephalomyelitis in mice

Experimental autoimmune encephalomyelitis (EAE) represents the mouse model of multiple sclerosis, a devastating neurological disorder. EAE development and progression involves the infiltration of different immune cells into the brain and spinal cord. However, less is known about a potential role of eosinophil granulocytes for EAE disease pathogenesis. In the present study, we found enhanced eosinophil abundance accompanied by increased concentration of the eosinophil chemoattractant eotaxin-1 in the spinal cord in the course of EAE induced in C57BL/6 mice by immunization with MOG35-55 peptide. However, the absence of eosinophils did not affect neuroinflammation, demyelination and clinical development or severity of EAE, as assessed in ΔdblGATA1 eosinophil-deficient mice. Taken together, despite their enhanced abundance in the inflamed spinal cord during disease progression, eosinophils were dispensable for EAE development.

Apoptosis of Eosinophil Granulocytes

In the past 10 years, the number of people in the Czech Republic with allergies has doubled to over three million. Allergic pollen catarrh, constitutional dermatitis and asthma are the allergic disorders most often diagnosed. Genuine food allergies today affect 6–8% of nursing infants, 3–5% of small children, and 2–4% of adults. These disorders are connected with eosinophil granulocytes and their apoptosis. Eosinophil granulocytes are postmitotic leukocytes containing a number of histotoxic substances that contribute to the initiation and continuation of allergic inflammatory reactions. Eosinophilia results from the disruption of the standard half-life of eosinophils by the expression of mechanisms that block the apoptosis of eosinophils, leading to the development of chronic inflammation. Glucocorticoids are used as a strong acting anti-inflammatory medicine in the treatment of hypereosinophilia. The removal of eosinophils by the mechanism of apoptosis is the effect of this process. This work sums up the contemporary knowledge concerning the apoptosis of eosinophils, its role in the aforementioned disorders, and the indications for the use of glucocorticoids in their related therapies.

Increased immune marker variance in a population of invasive birds

Immunity and parasites have been linked to the success of invasive species. Especially lower parasite burden in invasive populations has been suggested to enable a general downregulation of immune investment (Enemy Release and Evolution of Increased Competitive Ability Hypotheses). Simultaneously, keeping high immune competence towards potentially newly acquired parasites in the invasive range is essential to allow population growth. To investigate the variation of immune effectors of invasive species, we compared the mean and variance of multiple immune effectors in the context of parasite prevalence in an invasive and a native Egyptian goose (Alopochen aegyptiacus) population. Three of ten immune effectors measured showed higher variance in the invasive population. Mean levels were higher in the invasive population for three effectors but lower for eosinophil granulocytes. Parasite prevalence depended on the parasite taxa investigated. We suggest that variation of specific immune effectors, which may be important for invasion success, may lead to higher variance and enable invasive species to reduce the overall physiological cost of immunity while maintaining the ability to efficiently defend against novel parasites encountered.

Reactions of eosinophilic granulocytes in the sputum and peripheral blood of children suffering from bronchial asthma with signs of eosinophilic and non-eosinophilic inflammation of the bronchi

The aim of research was to improve the management of bronchial asthma in children by examining the peculiarities and diagnostic value of reaction markers of eosinophil granulocytes in the sputum and peripheral blood of patients with signs of eosinophil and non-eosinophil phenotypes of this disease. A cohort of 118 school-age children suffering from BA was examined during a period free from attacks. Group I (the main group ) included 61 schoolchildren with signs of eosinophil phenotype (EP) of asthma detected by the character of bronchial inflammation with eosinophil granulocytes present in the sputum at a level of >3%, group II (the comparison group) included 57 patients with a lower number of eosinophils in the sputum (non-eosinophil phenotype (NP) of BA). The average index of the relative content of eosinophils in the peripheral blood among the representatives of group I was 5.82 ± 0.63%, and in children with the signs of NPBA – 6.02 ± 0.74% (P > 0.05), and average indices in the groups of absolute eosinophil number in the blood were 0.37 ± 0.04 and 0.41 ± 0.05 respectively (P > 0.05). The negative reserve of NBT eosinophils in the sputum as a test to verify EPBA showed the following diagnostic values: specificity – 83.3%, predicted value of a positive result – 95.6%. IL-5 content in the blood serum of children with EPBA was 5.99 ± 1.74 ng/ml, in patients of group ІІ – only 1.99 ± 0.49 ng/ml (P < 0.05). Eosinophil cationic protein (ЕСР) in the sputum of patients of group I reached 2.72 ± 0.35 ng/ml, and in the comparison group – only 1.74 ± 0.34 ng/ml (P < 0.05), when the content of ECP in sputum was >1.0 ng/ml the risk of EPBA showed a statistically significant increase: OR = 4.13, RR = 2.02, and AR – 0.34. The efficacy of the standardized basic anti-inflammatory therapy in patients of clinical group I was higher as compared to the children with the signs of NPBA, which was illustrated by the reduced risk of inadequate control of the disease: the index of absolute risk decrease was 31.7%, relative risk – 57.1% with necessary minimal number of patients – 1.75.

Observations of Bordetella bronchiseptica infections in dogs

The aim of the study was to present and develop a comprehensive diagnosis of B. bronchiseptica infections in dogs from Lublin Voivodeship and to determine whether these animals were infected with one or multiple genotypes of the bacteria. Thirty-five dogs with bordetellosis confirmed by bacteriological and molecular tests were included in the study. Samples of blood for hematology and biochemistry, as well as bronchial alveolar lavage for cytological and molecular tests, were taken from all animals. Seven dogs showed a decreased hematocrit and a decreased number of red blood cells. In 16 dogs, leukocytosis was found. Increased AST activity, increased ALT activity, elevated serum concentrations of urea, and increased creatinine concentrations were observed in 3, 5, 3, and 3 dogs, respectively. Endoscopy showed inflammation in the trachea and bronchi in 15 dogs. Cytological examination of bronchoalveolar lavages revealed a large number of macrophages (in 18 dogs), lymphocytes (in 8 dogs), and eosinophil granulocytes (in 2 dogs). The genetic material of the bacteria, a fragment of Bordetella spp flaA gene, was detected in nasal and pharyngeal swabs taken from all 35 dogs, and in bronchial alveolar lavage from 17 dogs. A comparison of the nucleotide sequences of the gene showed that the homology between the bacterial isolates obtained in our study was 100%. This suggests the presence of only one B. bronchiseptica genotype in the dog population in Lublin Voivodeship. The sequence similarity of our isolates with sequences available in the gene bank (NCBI PubMed: EU 327790 from China, AJ 012319 from Argentina, L 13034 from the US) was also very high, ranging from 98.2% to 100 %. The results of our study indicate that a comprehensive diagnosis of the disease and its constant monitoring are necessary for recognizing the disease, for determining the relationship between the genetic structure of pathogens and the course of the disease, and for studying the immunoprophylaxis of B. bronchiseptica infections in dogs

PECULIARITIES OF THE FUNCTIONAL ACTIVITY OF BLOOD EOSINOPHIL GRANULOCYTES IN PULMONARY TUBERCULOSIS

Eosinophils are polyfunctional leukocytes detected in excess in blood and in the focus of granulomatous inflammation in pulmonary TB.The research objective was to evaluate the adhesive properties as well as cytokine-secretory and antibacterial activity of blood eosinophils in pulmonary TB.The research has been conducted on eosinophils isolated from peripheral blood of 43 patients with freshly identified progressive destructive TB with and without eosinophilia. Using flow cytometry and ELISA, expression of CD9 and CD18 adhesion molecules on blood eosinophils has been studied along with the phagocyte and cytokine-secretory functions and activity of eosinophil granulocyte peroxidase.As a result of the research it has been established that in TB patients with eosinophilia the number of CD18-expressing eosinophils rises, whereas the amount of CD9+ remains within norm. Activation of the phagocyte function of blood eosinophil granulocytes is associated with the decrease in eosinophil peroxidase activity, while the increase in IL-5 and TNFα secretory reactivity is connected with oppositely directed changes in IL-2 basal secretion by eosinophils in vitro (a fall in infiltrative TB and a rise in disseminated TB).

Testing, testing, testing: an insidious hypereosinophilia

Aim of the study: This case focuses on the difficulty in recognizing this rare entity characterized by systemic vasculitis in patients with history of asthma. Clinical case: We report a case of a 46-year-old man with history of allergic rhinitis and referred episodes of shortness of breath recognizing as acute bronchitis who presented with fever, skin eruption, peripheral eosonophilia, muscle weakness, abdominal pain and progressively dyspnea. Methods: Chest radiograph and computed tomography on admission showed consolidation in both lung fields and pericardial effusion. P-serum ANCA were positive. Neurological examination revealed mononeuritis multiplex. A skin biopsy was performed with presence of eosinophil granulocytes. The condition did not respond to antibiotics. He was supposed to have vasculitis and steroid treatment was started at a dose of 1 mg/kg; eosinophilia decreased but there was no clinical improvement. Abdominal pains were progressively more severe; emergency laparotomy revealed ileum infiammation, histopathological examination was consistent with Churg-Strauss syndrome.